Publications by authors named "Nathalie Lemiere"

Ultrasonic vocalizations (USVs) are used as a phenotypic marker in mouse models of neuropsychiatric disorders. Nevertheless, current methodologies still require time-consuming manual input or sound recordings clean of any background noise. We developed a method to overcome these two restraints to boost knowledge on mouse USVs.

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  • Hyperserotonemia, a common biochemical anomaly in autism spectrum disorders (ASD), has not been fully understood, prompting this study to explore serotonin sulfation by phenol sulfotransferases (PST) in blood samples from individuals with ASD and their families compared to controls.
  • The study found significantly reduced activity of two PST isoforms in platelets of ASD individuals, linking deficiencies in PST-M to higher serotonin levels and confirming similar deficits in pineal gland tissues, a key source of serotonin.
  • Although genetic analyses of SULT1A genes did not connect variations to PST activity or ASD risk, broader investigations revealed impairments in other sulfation markers, suggesting a generalized issue in sulfation metabolism that may explain hyperser
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Using human induced pluripotent stem cells (iPSC), recent studies have shown that the events underlying autism spectrum disorders (ASD) can occur during neonatal development. We previously analyzed the iPSC-derived pyramidal cortical neurons of a subset of patients with ASD carrying de novo heterozygous mutations in postsynaptic SHANK3 protein, in culture. We reported altered spinogenesis of those neurons.

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  • A study examined 357 individuals from the Faroe Islands, including 36 with autism, to explore genetic associations with the condition.
  • Findings showed that individuals with autism had a higher burden of rare genetic variants, inbreeding status, and more deleterious homozygous variants compared to non-autistic controls.
  • The research identified new potentially harmful gene variants related to autism and emphasized the need for further understanding of how these genetic factors influence neuronal function.
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The synaptic protein SHANK3 encodes a multidomain scaffold protein expressed at the postsynaptic density of neuronal excitatory synapses. We previously identified de novo SHANK3 mutations in patients with autism spectrum disorders (ASD) and showed that SHANK3 represents one of the major genes for ASD. Here, we analyzed the pyramidal cortical neurons derived from induced pluripotent stem cells from four patients with ASD carrying SHANK3 de novo truncating mutations.

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Autism spectrum disorders (ASD) are characterized by a wide genetic and clinical heterogeneity. However, some biochemical impairments, including decreased melatonin (crucial for circadian regulation) and elevated platelet N-acetylserotonin (the precursor of melatonin) have been reported as very frequent features in individuals with ASD. To address the mechanisms of these dysfunctions, we investigated melatonin synthesis in post-mortem pineal glands - the main source of melatonin (9 patients and 22 controls) - and gut samples - the main source of serotonin (11 patients and 13 controls), and in blood platelets from 239 individuals with ASD, their first-degree relatives and 278 controls.

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Jacobsen syndrome (JS) is characterized by intellectual disability and higher risk for autism spectrum disorders (ASD). All patients with JS are carriers of contiguous de novo deletions of 11q24.2-25, but the causative genes remain unknown.

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SHANK genes code for scaffold proteins located at the post-synaptic density of glutamatergic synapses. In neurons, SHANK2 and SHANK3 have a positive effect on the induction and maturation of dendritic spines, whereas SHANK1 induces the enlargement of spine heads. Mutations in SHANK genes have been associated with autism spectrum disorders (ASD), but their prevalence and clinical relevance remain to be determined.

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Inherited and de novo genomic imbalances at chromosome 16p11.2 are associated with autism spectrum disorders (ASD), but the causative genes remain unknown. Among the genes located in this region, PRRT2 codes for a member of the synaptic SNARE complex that allows the release of synaptic vesicles.

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Melatonin is a synchronizer of many physiological processes. Abnormal melatonin signaling is associated with human disorders related to sleep, metabolism, and neurodevelopment. Here, we present the X-ray crystal structure of human N-acetyl serotonin methyltransferase (ASMT), the last enzyme of the melatonin biosynthesis pathway.

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Autism spectrum disorders (ASD) are a heterogeneous group of neurodevelopmental disorders with a complex inheritance pattern. While many rare variants in synaptic proteins have been identified in patients with ASD, little is known about their effects at the synapse and their interactions with other genetic variations. Here, following the discovery of two de novo SHANK2 deletions by the Autism Genome Project, we identified a novel 421 kb de novo SHANK2 deletion in a patient with autism.

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Article Synopsis
  • * Researchers sequenced key melatonin pathway genes in 321 Swedish individuals, including 101 with ADHD and 220 controls, discovering damaging genetic mutations associated with ADHD.
  • * Notably, they identified specific mutations in the ASMT and MTNR1A genes that impair function and are exclusive to ADHD patients, marking the first detailed exploration of melatonin signaling issues in relation to ADHD.*
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Background: Autism spectrum disorders (ASD) are a group of severe childhood neurodevelopmental disorders with still unknown etiology. One of the most frequently reported associations is the presence of recurrent de novo or inherited microdeletions and microduplications on chromosome 16p11.2.

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Melatonin is a powerful antioxidant and a synchronizer of many physiological processes. Alteration of the melatonin pathway has been reported in circadian disorders, diabetes and autism spectrum disorders (ASD). However, very little is known about the genetic variability of melatonin receptors in humans.

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